Gulliksen's matched random subtests method is a graphical method to split a test into parallel test halves, allowing maximization of coefficient alpha as a lower bound to the classical test reliability coefficient. This problem is formulated as a zero-one programing problem solvable by algorithms that already exist. (TJH)

A simple probabilistic model for unfolding data collected by a direct response design in which responses were scored dichotomously was applied to the measurement of attitudes toward capital punishment. Responses conformed to the unfolding mechanism. Scale values of the statements were statistically equivalent to those of Thurstone's methods. (SLD)

A method of item factor analysis is described, which is based on Thurstone's multiple-factor model and implemented by marginal maximum likelihood estimation and the EM algorithm. Also assessed are the statistical significance of successive factors added to the model, provisions for guessing and omitted items, and Bayes constraints. (TJH)